Radiant heating panel



March 24, 1964 D. A. AITKEN ETAL.

RADIANT HEATING PANEL 3 Sheets-Sheet 1 Filed Oct. 11, 1962 INVENTORSEDav/d4. Airken David A. Ali/ken, Jn Ca/w'n M. Aifken BY 4 v i ATTORNEYSMarch 24, 1964 D. A. AITKEN ETAL 3,126,463

RADIANT HEATING PANEL Filed Oct. 11, 1962 3 Sheets-Shet 2 Call/inkAirken ATTORNEYS;

United States Patent ()fice A 3,126,468 Patented Mar. 24, 1964 3,126,468RADIANT HEATING PANEL David A. Aitken, Euclid, David A. Aitken, Jr.,South Euclid, and Calvin M. Aitken, Mayfield Heights, Ohio,

assignors to Aitken Products, Inc., Cleveland, Ohio, a

corporation of Ohio Filed Oct. 11, 1962, Ser. No. 229,803 13 Claims.(Cl. 219-34) This invention relates to radiant heating panels and moreparticularly to electrically energized radiant heating panels adaptedfor heavy industrial uses under adverse conditions.

In industrial facilities which require the use of coal or which areinvolved in the handling of ore or other aggregate material, the problemof thawing large carloads of this material during the winter months isvery acute. The use of fuel burners to thaw the contents of railroadcars is a past practice which is both undesirable from the standpoint ofexpense and dangerous in that it gives rise to detrimental effects onthe cars and other equipment.

The most recent development in this field provides a plurality ofinfra-red heating panels arranged in three banks, one on either side ofa railroad track and one located between the rails such as to besituated beneath a railroad car, the contents of which is to be thawed.The entire cluster of panels and the section of track are usually housedin a shed or the like so that some heat retention is provided in theimmediate area occupied by the car.

While the use of electric infra-red or radiant heating panels isinexpensive in theory and highly efiicient as to rate of heat transfer,a serious problem has arisen with respect to maintenance of the heatingpanels located beneath the railroad car. When the contents of the carbegin the thaw, the moisture frozen therein drains into the heatingpanels along with fines and other foreign matter which collect aroundthe heater elements and cause burnouts. Even quantities of material notsufficient to smother the heating elements will discolor and encrust thereflecting surfaces greatly reducing reflectivity and resulting inradiant heat loss.

In addition, the individual heating elements operating at sheathtemperatures of 1550 to 1650 degrees Fahrenheit under normal exterioroperating temperatures of to degrees Fahrenheit present problems ofunequal component expansion and contraction which creates buckling anddistortion of the heating panels.

The present invention deals with improvements in the type of radiantheating panel disclosed and claimed in our Patent No. 3,036,191 issuedMay 22, 1962.

It is a primary object of this invention to provide shielding means forthe terminal box of a heating panel whereby the terminals and wiringconnections contained in said box are protected against harmful heatradiation, the operating temperature of the heating elements imposed onthe terminals and wiring connections being thereby materially reduced.

Another object of this invention is to more adequately protect theterminal box from penetration of falling water by providing adrip-shield above the cover gasket of said box.

It is a further object to provide a novel reflector structure designedto permit easy assembly and removal without disturbing the heatingelements and their terminals.

Still another object of this invention is to mount the reflectorelements in such manner that thermal expansion and contraction of theparts will be permitted thus avoiding harmful distortion thereof.

These and other objects of this invention will become apparent withreference to the following specification and drawings which disclose apreferred embodiment of the invention.

In the drawings:

FIGURE 1 is a perspective view of the assembled radiant heating panel;

FIGURE 2 is an exploded view in perspective showing various parts innon-assembled condition;

FIGURE 3 is an end elevational view of the device with the end platepartially broken away;

FIGURE 4 is a fragmentary sectional view taken along line 4-4 of FIGURE3;

FIGURE 5 is a cross-sectional view taken along line 55 of FIGURE 1;

FIGURE 6 is a detailed sectional view taken along line 66 of FIGURE 3;

FIGURE 7 is a detailed sectional view similar to FIG- URE 6 relating toa modification; and

FIGURE 8 is a detailed cross-sectional view taken along line 88 ofFIGURE 6.

Referring in detail to the drawings, and more particularly to FIGURES 1,2 and 3, it will be seen that the structural frame of the heater 1consists of a pair of longitudinal center channel members 2, a pair oflongitudinal intermediate channel members 3, and a pair of longitudinalside channel members 4, all running parallel to the longest dimension ofthe heater, and all welded at one end to a combined baflle plate anddrip shield 5. The opposite ends of channel members 2 and 3 are likewisewelded to an end piece 6, while the opposite ends of the side channelmembers 4 are slidably secured to end plate 7 by bolts 8 and suitablelock nuts (not shown). To allow for thermal expansion and contraction,end plate 7 is provided with slots 9 formed in longitudinally extendingflanges 10 thereof. Bolts 8 pass through bolt hole openings 11 in sidechannel members 4 and are slidable in said slots 9. A pair of oppositelysloping angle bars 12 and 13 are welded to the inner vertical wall ofcombined baffle plate and drip shield 5 and a second set of similarlyarranged angle bars are welded to the inner wall of end plate 7.

The top of the frame is open to expose a plurality of coplanarhorizontally arranged U-shaped rods 14 or the like which comprise theelectric heating elements of the device, said rods 14 being supported bya plurality of laterally arranged elements 15, the latter in turn beingmounted at their ends in vertically disposed slots 16 in side channelmembers 4 and being loosely fastened therein. The upper edges ofsupporting elements 15 are provided with a plurality of notches 17 toaccommodate the U-shaped rods 14, said slots 16 and notches 17 allowingfor thermal expansion and contraction of the parts. The free ends ofrods 14- extend through appropriate openings 18 in the combined baffleplate and drip shield 5. As shown in FIGURES 2 and 5, a spacer strip orplate 19 is provided with similar openings 20 permitting the free endsof rods 14 to pass through like openings in the inner wall of terminalbox 21, said rods 14 terminating in conventional wire connections housedin the terminal box 21 and being secured therein by means of appropriatethreaded bushings 21a, washers and nuts. To reduce strain on theterminal connections, each rod 14 is provided with a stop member 22which engages the inner wall of baflie plate 5. If desired, greatersupport for the terminal box 21 may be provided by employing a pluralityof bolts 23, spacer washers 24 and nuts 25. A lead to an appropriateelectrical power source is shown at 25a in FIGURE 2. Terminal box 21 isequipped with a removable closure plate or cover 26 provided with arectan gular gasket 27 secured between the closure plate 26 andvertically disposed flange portions 28 of terminal box 21 by means ofcap screws 29 which terminate in and do not pass through bearing plates30, the inner walls of said bearing plates 39 engaging and being fixedto vertically disposed outer wall portions 31 of the terminal box 21.

Again referring to FIGURE 5, it will be noted that combined baflle plateand drip shield consists of an integral generally Z-shaped member havinga vertically extending end wall first portion 33 and a horizontal roofor second portion 34, the roof portion 34 terminating in a downwardlysloping lip portion 35. Foot portion 32 extends laterally inwardly fromthe lower edge of end wall first portion 33.

Referring particularly to FIGURES 1, 2, 3, 6 and 8, it will be seen thatthe reflector is divided into a pair of like plates 36 provided withintegral longitudinal inner flanges 37 and integral longitudinal outerflanges 38. Each plate 36-is provided with a series of slots 39 toaccommodate bolts 40. Loosely secured to each of said plates 36 andco-extensive therewith is an inverted U- shaped hold-down element 41.Said hold-down elements 41 are designed to be positioned over andslidably supported by intermediate longitudinal channels 3. Note, asshown at 42 in FIGURE 8 that there is appreciable space between theouter and inner vertically disposed wall portions of channels 3 andhold-down elements 41 respectively. Through bolts 43, with appropriatelock nuts 44, are inserted through hold-down elements 41 to maintainloose engagement of hold-down elements 41 with the intermediatelongitudinal channels 3. Numeral 45, see FIGURE 2, designates a pair ofhold-down angle members each of said members consisting of a verticalleg 46 and a horizontal downwardly sloping leg 47, vertical legs 46being provided with a series of bolt-receiving openings 48; the purposeand function of hold-down angle members 45 being later described.

Referring to FIGURE 7 a modified arrangement of reflector hold-downmember is disclosed. Instead of utilizing a single elongated hold-downelement 41 for loosely connecting reflector plate 36 to intermediatelongitudinal channel 3, the structure may be modified to provide aplurality of inverted U-shaped clips 49. Suitable bolts and lock nuts 50secure the U-shaped clips 49 to the reflector plate 36, and in thismodified form of the invention slots 39 used in the preferred embodimentare not required. Clips 49 are maintained in loose engagement withintermediate channel members 3 by means of through bolts 51 and locknuts 52 in a fashion similar to that already described with reference tothe preferred embodiment, appreciable spacing being again providedbetween said clips 49 and said channel members 3 to allow for expansionand contraction.

In assembling the radiant heating panel of this invention, the channelmembers 2, 3 and 4 are all welded at one end to combined baflle plateand drip shield 5 said channel members 2 and 3 being likewise welded attheir other ends to end piece 6, angle bars 12 and 13 having alreadybeen welded to said baffle plate 5. The heating elements 14 are theninstalled being supported by the laterally disposed elements 15 mountedin side channel members 4, said heating elements 14 passing throughbaflie plate 5 and spacer plate 19 and being suitably secured interminal box 21, the latter being rigidly supported by baflle plate 5,but in spaced relation thereto by virtue of the interposition of spacerplate 19. Additional support for the terminal box may be provided bybolts 23. As described up to this point, the assembly of the sixlongitudinal channel members, the baffle plate and the terminal box,with heater elements and heater element supports installed, should bevisualized as a solid, permanent entity. In general this assembly willremain as described for the life of the heater, except that a burned outheating element may be changed occasionally.

The remaining parts now to be assembled are characterized by the factthat they may be readily installed and removed and their manner ofassembly and connection with the rigidly assembled frame work allows fordifferences in thermal expansion and contraction. The reflector plates36 are mounted on the frame by sliding them under the heating elements14 and their supports 15 and positioning the inner flanges 37 betweenthe vertical legs of channel members 2 with the hold-down elements 41loosely engaging channel members 3, the ends of the reflector plates 36adjacent bafile plate 5 being received beneath and held down by anglebars 12 and 13. Holddown angle members 45 are then inserted between andabove the center mating line of the reflector plates 36,

and pinned in place by means of bolts 53 which pass through the verticallegs of channel members 2 and the vertical legs 46 of angle member 45,it being noted however that bolts 53 do not pass through inner flanges37 of reflector plates 36. Next the end plate 7, having welded to itsinner wall a like pair of oppositely sloping hold-down angle bars 12 and13, is solidly bolted to end piece 6 and slidably bolted to side channelmembers 4 by means of slotted flanges 10, the ends of reflector plates35 adjacent end plate 7 being slidably received beneath said hold-downangle bars 12 and 13.

With the assembly completed it can be seen that the reflector plates 36are free to expand uniformly or nonuniformly in all directions and yetare confined by holddown angle members 45 at the center, hold-down anglebars 12 and 13 at the ends, and hold down elements 41, or hold-downclips 49 in the modified form of FIGURE 7, loosely engaging intermediatelongitudinal channel members 3. Expansion and contraction of the variouslongitudinal channel members 2, 3 and 4 is permitted by the slots 9 inthe flange members 10 of end plate 7.

Of particular importance is the combined baflle plate and drip shield 5provided with the spacer plate 19 be tween said plate 5 and terminal box21. By use of bafile plate 5 and spacer plate 19, the terminal box 21 isshielded from harmful heat radiation prolonging the useful life of theterminals and wire connections resulting in great savings and renderingfrequent replacement of said parts unnecessary.

It will be further noted that roof portion 34 and lip portion 35 ofbaflle plate 5 extend over the top wall and closure plate 26 of theterminal box 21 whereby said box and its contents are protected againstfalling debris and water damage.

It will also be appreciated that the reflector plates 36 are so mountedthat they may be readily removed and replaced if damaged or discolored.Further, the sloping design of the reflector plates 36 when in assembledposi tion and their outer flanges 38 provide means whereby spillage fromoverhead may be properly drained away.

In the preferred design, all parts are made of aluminum with theexception of the heater element supporting members which are made ofstainless steel.

It is to be understood that the embodiments shown and described hereinare for the purpose of example only and are not intended to limit thescope of the appended claims.

What is claimed is:

l. Radiant heating panel means for thawing ice or the like fromsuperimposed objects, comprising an open-topped horizontal rectangularframe including a pair of longitudinal side walls and a vertical endwall having a vertical first portion;

a plurality of generally coplanar horizontally-arranged verticallyupwardly exposed electrical heating elements supported in said frame;

means supplying electrical energy to said heating elements including acompletely enclosed terminal box having a vertical side wall adjacentand spaced from the external surface of said end wall first portion, andconductor means in said terminal box;

spacer means intermediate said end wall and said terminal box side wall,said spacer means extending horizontally along said terminal boxvertical side wall and being arranged substantially coplanar with saidheating elements;

and means rigidly connecting said terminal box with said end wall, eachof said heating elements including at least one terminal portionextending into said terminal box through aligned openings in saidvertical first wall portion, said spacer means and said terminal boxside wall for connection with said conductor means, the end wall of saidframe including at its upper edge a horizontal second portion extendingcompletely across said terminal box, and a downwardly inclined lipportion connected with the free edge of said second portion, whereby theend wall of said frame constitutes a baflle plate and drip shield forprotecting said terminal box against radiant heat and falling particlesand liquids.

2. A radiant heating panel comprising a horizontally-arrangedrectangular frame including a generally vertical end wall, a pair ofparallel longitudinal side channel members, a pair of longitudinalcenter channel members intermediate and parallel with said side channelmembers, a pair of longitudinal intermediate channel members each ofwhich is arranged between, parallel with and spaced from one of saidlongitudinal center channel members and the adjacent longitudinal sidechannel member, each of said channel members being rigidly secured atone end to said end wall, a vertical end piece rigidly secured to thefree ends of said pairs of center and intermediate channel members, anend plate adjacent the free ends of said side channel members and on theopposite side of said end piece from said end wall, and means slidablyconnecting said end plate with the free ends of said side channelmembers to permit movement of said end plate longitudinally of saidframe;

a plurality of horizontal coplanar electrical heating elements mountedin said frame above said center and said intermediate channel members;

and longitudinally extending reflector means supported on said centerand said intermediate channel members below said heating elements.

3. Apparatus as defined in claim 2 wherein said means slidablyconnecting said end plate with said side channel members comprises apair of vertical flange portions on said end plate extending adjacentand parallel with the free end portions of said side channel members,one of said portions including longitudinally extending slots and theadjacent cooperating portion including bolt means extending through saidslots for slidably connecting said flange portions with said sidechannel members.

4. Apparatus as defined in claim 3 wherein said reflector means includesa pair of longitudinally extending reflector plates on opposite sides ofthe longitudinal center line of said firame, each of said reflectorplates being supported by one of said center channel members and theassociated intermediate channel member.

5. Apparatus as defined in claim 4 wherein each of said reflector platesis slightly inclined about its longitudinal axis relative to thehorizontal, the longitudinal edge of said reflector plate adjacent thecenter channel member being at a higher elevation than the otherlongitudinal edge.

6. Apparatus as defined in claim 5 wherein said reflector plates have atone end transverse edge portions that extend above said end piece andterminate adjacent said end plate, said reflector plates having at theother end transverse edge portions that terminate adjacent said endwall; and further including hold down means controlling the verticalmovement of said reflector plates relative to said frame, said hold downmeans comprising hold downbar-s secured to the adjacent surfaces of saidend wall and said end plate, said hold down bars being arranged forcontiguous coextensive engagement with the upper surfaces of thetransverse edge portions at each end of each of aid reflector plates.

7. Apparatus as defined in claim 6, wherein said hold down means furtherinclude auxiliary means loosely connecting said reflector plates withsaid intermediate channel members to permit free longitudinal movementand limited vertical and transverse movement of said reflector platesrelative to said intermediate channel members.

8. Apparatus as defined in claim 7 wherein said auxiliary hold downmeans comprises longitudinally arranged inverted U-shaped channelelements connected with the lower surfaces of said reflector plates andreceiving said intermediate channel members, and transverse pin meansextending between the flanges of said U-shaped channel elements belowand spaced from said intermediate channel members.

9. Apparatus as defined in claim 8 wherein the auxiliary hold down meansassociated with each of said reflector plates comprises a singlecontinuous U-shaped channel element, and pin and slot means connectingsaid U-shaped channel element with said reflector plate to permitrelative longitudinal movement therebetween.

10. Apparatus as defined in claim 8 wherein the auxiliary hold downmeans associated with each of said reflector plates comprises aplurality of aligned, longitudinally spaced U-shaped channel elements.

11. Apparatus as defined in claim 8, wherein each of said reflectorplates includes a longitudinal downwardly extending flange portionextending between said center channel members, and further wherein saidhold down means includes a generally T-shaped hold down member havingupper flange portions extending above and in contiguous coextensiveengagement with the adjacent upper longitudinal surfaces of saidreflector plates, said T- shaped hold down member having a verticalportion extending downwardly between and beyond the adjacent flangeportions of said reflector plates, and pin means connecting the lowerend of the vertical portion of said T-shaped hold down member thatextends below said reflector flanges with said center channel members.

12. Apparatus as defined in claim 11 wherein said T- shaped memberconsists of a pair of angle arms having abutting legs.

13. Apparatus as defined in claim 8 wherein the end wall of said frameincludes a vertical first portion; and further including means supplyingelectrical energy to said heating element comprising a terminal boxhaving a vertical side wall adjacent and spaced from the externalsurface of said end wall first portion, and conductor means in saidterminal box; spacer means intermediate said end wall and said terminalbox side wall; and means rigidly connecting said terminal box with saidend wall and said spacer means, each of said heating elements includingat least one terminal portion extending into said terminal box throughaligned openings in said vertical first wall portion, said spacer meansand said terminal box side wall for connection with said conductormeans, the end wall of said frame including a horizontal second portionconnected with the upper edge of said first portion and extendingsubstantially completely across said terminal box.

References Cited in the file of this patent UNITED STATES PATENTS1,892,298 Bray Dec. 28, 1932 2,259,143 Shroyer Oct. 14, 1941 2,843,716Del Francia July 15, 1958 2,877,332 Senior Mar. 10, 1959 FOREIGN PATENTS321,065 Great Britain Oct. 31, 1929 119,936 Australia May 7, 1945

1. RADIANT HEATING PANEL MEANS FOR THAWING ICE OR THE LIKE FROMSUPERIMPOSED OBJECTS, COMPRISING AN OPEN-TOPPED HORIZONTAL RECTANGULARFRAME INCLUDING A PAIR OF LONGITUDINAL SIDE WALLS AND A VERTICAL ENDWALL HAVING A VERTICAL FIRST PORTION; A PLURALITY OF GENERALLY COPLANARHORIZONTALLY-ARRANGED VERTICALLY UPWARDLY EXPOSED ELECTRICAL HEATINGELEMENTS SUPPORTED IN SAID FRAME; MEANS SUPPLYING ELECTRICAL ENERGY TOSAID HEATING ELEMENTS INCLUDING A COMPLETELY ENCLOSED TERMINAL BOXHAVING A VERTICAL SIDE WALL ADJACENT AND SPACED FROM THE EXTERNALSURFACE OF SAID END WALL FIRST PORTION, AND CONDUCTOR MEANS IN SAIDTERMINAL BOX; SPACER MEANS INTERMEDIATE SAID END WALL AND SAID TERMINALBOX SIDE WALL, SAID SPACER MEANS EXTENDING HORIZONTALLY ALONG SAIDTERMINAL BOX VERTICAL SIDE WALL AND BEING ARRANGED SUBSTANTIALLYCOPLANAR WITH SAID HEATING ELEMENTS; AND MEANS RIGIDLY CONNECTING SAIDTERMINAL BOX WITH SAID END WALL, EACH OF SAID HEATING ELEMENTS INCLUDINGAT LEAST ONE TERMINAL PORTION EXTENDING INTO SAID TERMINAL BOX THROUGHALIGNED OPENINGS IN SAID VERTICAL FIRST WALL PORTION, SAID SPACER MEANSAND SAID TERMINAL BOX SIDE WALL FOR CONNECTION WITH SAID CONDUCTORMEANS, THE END WALL OF SAID FRAME INCLUDING AT ITS UPPER EDGE AHORIZONTAL SECOND PORTION EXTENDING COMPLETELY ACROSS SAID TERMINAL BOX,AND A DOWNWARDLY INCLINED LIP PORTION CONNECTED WITH THE FREE EDGE OFSAID SECOND PORTION, WHEREBY THE END WALL OF SAID FRAME CONSTITUTES ABAFFLE PLATE AND DRIP SHIELD FOR PROTECTING SAID TERMINAL BOX AGAINSTRADIANT HEAT AND FALLING PARTICLES AND LIQUIDS.